1990 Mercedes-Benz W124 Reviews

1990 Mercedes-Benz W124 300E M103 petrol from Italy

Faults:

By moving to KE-Jetronic - due to the anti-pollution norms - Mercedes-Benz probably has lost part of its legendary reliability. This is, at least, my thought.

Electronics are a nightmare: first failure was the EHA sensor, making the car prone to stop randomly and suddenly at every speed. No way to switch on the engine before 5 minutes to 15 minutes max; I had to wait for that random time, then the engine ran smoothly like nothing had happened. This issue required a long examination to be found by the authorized Bosch workshop, being able to find the root cause and substitute the EHA for 400 Euro (an additional 8h of manpower was added to the final bill).

Months later, the potentiometer of the mass flow sensor was the root cause of a rough running at idle and up to 2000 revs; sometimes the car was going to stop (this last one cannot be replaced, you need the mass flow sensor new, which costs 10 times the potentiometer). I paid 208 Euro for a revised unit and 6h of manpower to search for the root cause.

I was obliged to change both the roller bearings of 5th gear, otherwise rough running - like you are traveling over a rough concrete surface - was present between 100 to 130 km/h: you can guess how terrible a motorway trip was at 140/150 km/h, risking a fine, or living hours at 90 km/h with a truck on your back and another one in front of you.

Unbelievable - in a Mercedes-Benz - that the plastic covers of the rear lights cracked (even if not broken): I understands 20 years of sunlight, but how does my previous BMW after 30 years have no damage, even if very small?

General Comments:

I bought this car because of its 138000 km in 20 years: a warranty of the real odometer mileage was its first owner, who sold to me informing me that he kept the car stopped in a garage for 95% of time in the last 6 years (2004 to 2010) because of the use of a city car after his retirement. This obliged me to have a full service of the 300 E, but probably it was not sufficient to neutralize the bad effect of the long stop, which contributed to the reliability failures.

Another reason for buying was it had plenty of options: automatic conditioned air, leather seats, front power seats, power windows, power sunroof, central locking and a lot of minor gadgets. To be demanding, only automatic transmission and light alloy wheels were missing.

Great comfort: during city running you are not able to feel any noise, unless you turn the engine at high revs (more than 4000), which is not possible in a town street. On a highway journey, you can hear only the tire sound, being the air noise is present only over 130 km/h and engine roaring only after 4000 revs (about 160 km/h in 5th gear).

Also economy is fairly good for a car of its size: highway trips at 130 km/h require 9.5-10 liters for 100 km, and town use requires 7.5 to 8.5, which is already good for its size and time.

Driving is good, but I feel a heavier behavior in comparison with the more reactive BMW 528i handling; steering is more precise, but it seems I'm at the wheel of a vehicle having 400 or 500 kg more than the BMW, while the difference is 100 kg only. Despite that, the 300 E is largely gaining in stability compared to the 528i; what you need to pay in pleasure, you gain in safety.

Carriage is very good for people, while the boot - even very large - is taller than deeper; this implies the smaller 528i one is more practical to carry long objects, being not so tall but very large and deep.

Climatic automatic control could be better: the six buttons on the center console do not allow you to have a mixed air flow, for example a combination of air flow to the windscreen and to the legs, which is allowed by the manual controlled air conditioning. A couple of additional buttons - one to mix upper and lower flows, one to mix lower and front flows - would get the automatic control clima equivalent to the manual one in terms of possibility.

26th May 2018, 11:58

I had a 1985 Audi 80 1.8 GTE which had that problem re: not wanting to start for 5-15 minutes. Problem was the engine control relay - a hairline crack in the solder inside the relay. Once fixed, never gave problems again.

Emissions compliance unfortunately continually adds complexity to all cars. Electronics fortunately are fairly dependable, but unlike older fully-mechanical components, sensors for example are very complex yet packed into a tight package, fitted to parts of the engine which are prone to extreme heat then cold (or wet). In the old days, Mercedes could simply design a spring or diaphragm, or whatever, and simply engineer it to a more conservative design - thicker or better-grade steel, higher torque rating, whatever - and charge the cost for it, and it simply doesn't break. But sensors, for instance, don't come in several grades of "quality" - they are designed to do a purpose, and there's no such thing as a higher-grade computer chip doing a certain function, with higher quality solders, just because it's Mercedes. They are all the same. Japanese electric components fare better, I think, but even they can fail with time. Car makers can give a 20-year anti-corrosion warranty because metal, paint, wax and rustproofing can be designed to a standard. But what good is a galvanised body good for 20 years, if a sensor or assembly costs $4,500 to replace... on a car only worth $5-6K?

1990 Mercedes-Benz W124 260E 2.6 M103 from UK and Ireland

Summary:

Faults:

For a 26 year old vehicle that is used on a regular basis, amazingly nothing has gone wrong that has prevented my use of the vehicle.

I have carried out some required maintenance to the vehicle, including replacing most of the front suspension.

General Comments:

If you haven't driven a Mercedes from this era, you really should. I previous to buying this car had driven all manner of "top of the range" Ford and Vauxhall etc, which profess to be luxury vehicles; I can state quite categorically they are not even in the same league as a proper Mercedes. You just have to drive one to really understand. Bear in mind my W124 was bought for £495 with galactic miles on the odometer; having never driven one I didn't expect much, but WOW, my first drive out of the forecourt was shocking, it literally glides over the road surface, it irons out undulations and potholes like you would not believe, it feels very heavy, but not in a bad way.

It's like being surrounded by several feet of concrete, but at the same time cushioned by the finest quality German leather and wood; all this with 26 year old suspension components that were at best in dire condition. I lived with it for a while, but driving above 55 mph really took away that special driving experience, as it was like trying to sail a yacht across the English channel. Eventually I did change all the front suspension links and control arms, and now it tracks beautifully up to 100 mph and rides even better.

It is not equipped well up to today's standards, but luxury cars back in the 80s and 90s weren't all about gadgets, it was about providing the most comfortable, cossetting place to be, and that's what Mercedes did with this car.

The engine is another surprise, it is utterly smooth; by smooth I'm talking balancing a 20 pence on the cam cover at 2000 RPM and it will sit motionless; this combined with the superb ride makes for an uncompromisingly comfortable car to drive, although when you need to push on, the 6 cylinder engine does make a certain roar that is very much unlike the odd sound that comes out of someone's Vauxhall Astra with a stupidly enormous backbox exhaust; it sounds like it means business.

It's a shame then in this regard the 2.6 M103 never really delivers; it has the bark but not much bite, 166BHP when new and you really have to work it when pushing on; kickdown is necessary to overtake and accelerate quickly pretty much all the time; there really is not much low down torque, mid range is acceptable, but for a single OHC engine, the power is unusually near the top end. Now combined with a decent manual gearbox, this wouldn't necessarily be a problem, because at least the engine sounds good, however the automatic gearbox here is rather a lazy contraption that does suck quite a lot of power; it is not keen to change down on time; for example when you're pulling onto a motorway slip road uphill, you find yourself using kickdown.

It is however in keeping with the rest of the car, and changes up and down very smoothly. It's probably an unfair to be so harsh towards the drivetrain after nearly a quarter of a million miles, and it is very reliable, so I forgive it for its lack of power; after all, it is not a sports car and has never tried to be one.